SU577249A1 - Alloy for deoxidizing and alloying steel - Google Patents

Description

one

The invention relates to steelmaking, in particular to alloy compositions used for deoxidation and alloying.

Known alloy for cast iron processing

and steel containing, wt.%: Vanadium 5-14; silicon 5-ZO; manganese 5-25; chrome 1,0-З, О; titanium 0.1-2.0; carbon 0.2-4.0; nitrogen 0.01-0.4; iron rest | l

Also known alloy, wt.% Molybdenum 5-ZO; vanadium 5-2O; silicon 5-1O; manganese 2-10; carbon 0.5-3.5; chromium 0.5-3.0; titanium 0.5-5.0; iron - the rest 2.1.

However, the known alloys do not provide sufficient oxidation and purity of the steel, which makes it necessary to use aluminum in its pure form. As a result of this deoxidation, the metal has an increased contamination with oxide inclusions.

The aim of the invention is to create an alloy for deoxidation and alloying, using which one provides an improvement in the quality of steel by reducing the pollution of

its oxide nonmetallic inclusions, reducing gas saturation, ensuring homogeneity of the chemical composition, as well as increasing its strength characteristics.

This is achieved by the fact that aluminum is additionally introduced into the alloy with the following ratio of components, wt.%:

Aluminum4-8

Carbon 2.5-5

Vanadium0,2-15

Manganese 0.1-2 5

Silicon, 1-2O

Chrome 0.1-4

Titanium 0.1-4

Iron Else.

When deoxidized with metallic aluminum due to its low specific weight, deoxidation occurs at the interface between the metapp atmosphere .. This leads to significant oxidation of aluminum due to atmospheric oxygen and contamination of the steel with oxidation products.

When using an aluminum alloy with heavier elements based on iron, steel is deoxidized with aluminum in the bulk of the metal, as a result of which the amount of aluminum oxidation products is sharply reduced.

The introduction of carbon into the alloy within the specified limits leads to a decrease in its melting temperature in comparison with the temperature of the known carbon-free and low-carbon alloys by 150-2SO ° C, which ensures uniform distribution of the alloy components in the steel volume. At the same time, the increased carbon content contributes to a more active removal of CO from the metal and, consequently, a decrease in the content of gases and non-metallic: inclusions.

To increase the strength characteristics of the steel, vanadium is introduced into the alloy. RELATING the alloy in the smelting of high and medium carbon structural steel contributes to its quality, umansheniyu hydrogen concentration by 25%, increasing the degree of deoxidation (reducing the oxygen content by 30%), improving the macro and microstructure, reducing the content of non-metallic inclusions, especially oxide type AE. ABOUT .

The use of the alloy reduces At n V carbon loss by 20–30% compared with the use of metallic aluminum and vanadium outside the alloy with the latter, while the consumption of Te Si and Te Mn is also reduced in quantities proportional to the content of manganese and silicon in the proposed alloy. In a splash, it is necessarily simultaneous, the presence of aluminum, carbon and vanadium in predetermined ratios.

The choice of limits on the content of components in the alloy is due to the following considerations:

For aluminum - the introduction of aluminum in steel, depending on the brand in the range of 0.01-0.06% (100-600 g / t). With less aluminum consumption, the necessary oxygen binding is not ensured. Oxygen in a solid solution leads to a decrease in ductility and toughness. With a higher content of aluminum, the surface of the ingot is known to be thickened and tightened by a metal stream during casting.

According to carbon - to give the alloy a low melting temperature, the minimum of which according to the T-C state diagram is in the range of 2.5-5.0% C. The maximum temperature range of the crystalline darks of the proposed alloy, taking into account the content in it, another 4-8 AU em

1150 (solidus) - 1280 С (liquidus), against the crystallization temperature of the same, but carbon-free alloy - about 140О-1450 С.

For vanadium, to produce low-vanadium steels with an optimal level of mechanical properties. When the content of the alloy in the alloy is less than 0.2% V (0, O1% V in the metal, the steel does not harden; when the content in the alloy is more than 15% V (more than 0.1% in the metal), the ductility and toughness of the steel decrease.

For the remaining components (Mn, Si and Ct, Ti, Ve.) The chemical composition of the raw material used to obtain - the proposed alloy.

Example. The metal is treated with an alloy containing, wt.%: Aluminum 7,8; a perper 4.7; vanadium 4.8; manganese 15; silicon 11.1; chromium 3; titanium 3; iron ostal As a result of processing, oxen were obtained in the metal, valuable inclusions were 1-2 points, aluminum loss of 36%, vanadium loss of 0%

PRI mme R 2. Metal treated sgshavom containing, wt.%; aluminum 6.2; perger 3.9; vanadium 4.5; manganese 15; silicon 11, 1; chromium 3; titanium 2.4; iron rest. As a result of processing, oxide inclusions of 1-2 points were obtained in the metal, aluminum loss of 37%, Vanadium burn of O%, Example 3. The metal is treated with an alloy containing, wt%; aluminum 3.95 carbon 2.8; vanadium 4.2; manganese 13.6; silicon 9.0; chromium 3.0; titanium 2.0; iron ostal As a result of processing, B metal oxide inclusions of 1-2 points were obtained, the loss of aluminum was 40%, the loss of vanadium was 0%.

When metal is processed with known alloying materials, and the loss of aluminum reaches 76%, the loss of vanap1 is 26%, and oxide inclusions are 4–5 points.

Claims (2)

Invention Formula Shrinking to deoxidize and alloy steel, containing carbon, vanadium, manganese, silicon, chromium, titanium, and iron, characterized in that it also contains aluminum in the following ratio of components, wt.% To improve the quality of the steel being treated; Aluminum4-8 Carbon 2.5-5 Vanadium0,2-15 Manganese 0.1-25 Silicon0,1-20 Chrome-0.1-4 j Titanium-0.1-4 IronEsaltial Sources of information accepted during examination: 577249 1. Author's guide SSSSRM 451779, c.C22C35 / OO, 1973. look down 2. Avgorskoe LitovskopilstvSSSSR №451781, Vol. C 22 C 35 / OO, 1973.